Device for adjustment of a vehicle seat, and a base frame for a vehicle seat

ABSTRACT

In an arrangement for a seat ( 2 ) in a vehicle, the seat is movable in a longitudinal direction along a plane ( 33 ) which slopes relative to the horizontal plane. The subframe of the seat ( 2 ) consists of devices ( 30, 31 ) fastened respectively to the vehicle and to the seat, which devices consist of two substantially similar triangular supporting frames. Resetting between a predetermined driving position and a likewise predetermined resting position is made possible by a control device ( 16 ) which is fastened to the device ( 30 ) which is itself fastened to the vehicle, which control device cooperates with a locking device fastened to the seat so that during a relocating movement between forward and rear positions of the seat the locking device ( 17 ) becomes free from at least one locking position between the vehicle seat and the device ( 30 ) fastened to the vehicle.

BACKGROUND OF THE INVENTION

The present invention relates to an arrangement for enabling a vehicleseat to be moved forward and rearwardly, to be locked in a forwardoperating position and to be readily unlocked for rearward movement anda subframe which is fastenable to the vehicle floor below it and to theseat above it, which permits the seat to slide forward and rearward,which enables. the seat to be locked in a forward position and whichenables the seat to be moved rearwardlye.

STATE OF THE ART

A generally known arrangement is for vehicle seats, particularly drivingseats, to be movable in the longitudinal direction of the vehicle inorder to make convenient positioning possible for the seat user and/orcreate more clear space in the interior of the vehicle. In such casesthe seat is usually mounted on longitudinal rails situated in a planewhich either slopes somewhat upwards in the forward direction of thevehicle or substantially horizontally. This consequently makes itpossible to move the seat along the corresponding plane. Such anarrangement does limit, however, the possibility of easily climbing intoand out of the vehicle and getting into and out of the vehicle seat,particularly in vehicles of the truck and bus type. Operating the seatsecuring mechanism for manual setting of the seat in the longitudinaldirection also involves control action during the whole setting movementand often entails one or more extra setting movements before the desiredsecuring position is reached.

BRIEF DESCRIPTION OF THE INVENTION

The object of the present invention is to provide a seat arrangementthat manifestly reduces the abovementioned disadvantages of the state ofthe art. The invention aims at seat control which, particularly in truckcabs, makes it easy to reset the seat between a predetermined drivingposition and a likewise predetermined resting position not intended tobe a driving position. The solution has also to make possible a simpleform of control mechanism with simple and inexpensive components withouthaving to disregard the safety requirement of reliable securing of theseat.

To this end, the invention is distinguished by a control device thatcooperates with the seat locking device during relocation of the seatbetween the forward and rear positions, freeing the locking device froma locking position to free the seat to move to the rear position. Thefeatures therein indicated makes it possible for the seat to be providedwith a longitudinal relocating movement between a forward (driving)position and a rear (resting) position by easy manual operation of acontrol which acts upon the seat locking device. Rail mechanisms ofstandard types which are simple, inexpensive but well-proven from thesafety point of view can be used for the purpose. The co-operationaccording to the invention between control device and locking devicealso makes it possible to reset the seat quickly and safely betweenpreselected forward and rear positions. This solution is particularlyadvantageous in the case of seats of the type which can be relocatedalong a plane which slopes downwards in the forward direction of thevehicle. Such seats are used with advantage in vehicles of the truck andbus type which are entered by climbing and in which it is possible tosit down in the seat from an almost standing position.

In an advantageous embodiment of the invention, the seat can be movedrearwards with the assistance of a first force to a rear (resting)position. This makes it possible for a person sitting in the seat tocause it to move to a rear position by simply lightening his weight onthe seat and by operating manually the control which acts upon thesecuring mechanism.

In another embodiment, the seat can be moved forwards, i.e. from therear position to a forward (driving) position, against the action of asecond force. This means that in the case of seats of the aforesaid typewhich can be moved along a plane which slopes downwards in the forwarddirection of the vehicle, the movement can take place against the actionof the second force so that when a person sits on the seat while it isat an upper resting position the seat will automatically, by acontrolled movement, assume a driving position.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the invention is described below withreference to the attached drawings, in wich:

FIG. 1 shows schematically a side view of a vehicle cab with a seatarrangement according to the invention,

FIG. 2 shows a perspective view of a seat subframe according to theinvention,

FIG. 3 shows a schematic arrangement according to the invention formutual locking of the subframe components, and

FIG. 4 shows the same view as FIG. 1 with the seat arrangement at adifferent height.

DESCRIPTION OF PREFERRED EMBODIMENT

A truck cab 1 is depicted schematically in FIG. 1. A driver's areacontains a driving seat 2 with a subframe 3 which is fastened to the cabfloor 4. The seat 2 can be moved in the longitudinal direction of thevehicle from a forward (driving) position 5 to a rear (resting) position6 which is not intended to be used when the vehicle is being driven.FIG. 1 shows only the subframe 3 in the resting position, but it isimplicit that when moving to the rear position 6 the subframe 3 isaccompanied by the seat 2 with its frame 35. A pedal set 8, a steeringwheel 9 and an instrument panel 10 are situated in a conventional mannerin front of the seat. A gear lever 11 and a lever 23 forming part of asecuring device 15 (depicted in FIGS. 2 and 3) according to theinvention are situated to the side of the seat. An engine cover 12 alsoprotrudes into the cab and to some extent separates the driving sidefrom the passenger side.

The subframe 3 is composed advantageously of two substantially similarelements 30,31, each of which has a triangular shape in the verticalplane (see FIG. 2). Each element is composed of two triangularsideplates whose sides, which are short catheti, are joined together byan endplate 38 and, at the opposite end, by the corner sections of anangle plate 39. The underside of the element 30, which is a cathetus, isintended to be fastened to the vehicle floor, advantageously byundepicted screws or bolted connections. The hypotenuse side of theelement 30 bears a rail device 32 a in the form of a rail on eachtriangular sideplate. The rail device 32 a forms a plane 33 which slopesrelative to the horizontal plane and which is represented in FIG. 1 by achain-dotted line. The subframe 3 and its elements 30,31 are so arrangedthat the sloping plane 33 slopes downwards in the forward direction ofthe vehicle.

The hypotenuse side of the upper element 31 correspondingly bears a raildevice 32 b for cooperation with the rail device 32 a of the lowerelement 30. The top of the upper element 31 supports a rail device 32 c(depicted in FIG. 1) for co-operation with a corresponding rail deviceon the underside of the frame 35. Said co-operation makes a longitudinalrelocating movement possible along the horizontal plane 34 formed bythese rail devices, which is represented in FIG. 1 by a chain-dottedline. All the rail devices 32 a, 32 b and 32 c are of a conventionalstandard type which has toothed recesses for locking in variouspositions at will and which conform to stringent safety requirements butare described in no further detail here. FIG. 3 shows schematically therail devices 32 a,32 b with roller devices 27 for easy frictionlesslongitudinal relocating movement between the elements 30,31.

A return spring 40, advantageously in the form of a gas spring asdepicted in FIG. 2, is arranged between the forward end portion of thelower element 30 (as seen in the forward direction of the vehicle) andthe rear end portion of the upper element 31, preferably in alongitudinal symmetry plane between their angle plates 39. When theupper element 31 is in the forward end position 5 (depicted in FIGS. 1and 2) relative to the lower element 30, the gas spring is in acompressed state. In that situation, the mechanical securing device 15which locks the elements 30,31 to one another prevents the gas spring 40from pushing the upper element 31 upwards and rearwards along the rails32 a,32 b.

In an advantageous embodiment of the securing device 15 according toFIGS. 2 and 3, a running track 16 fastened to the lower element 30(which is itself fastened to the vehicle) co-operates with a rear endsection 50 of a locking device 17. The latter is supported for pivotingabout a spindle 41 on the upper element 31 and incorporates on eitherside of the seat a locking part 44 and a yoke 43 which is fastenedthereto by separate fastening devices 46 and which is entered by therear end section 50. The yoke 43 consequently extends between the twosides of the upper element 31, and the two locking parts 44 are eachsupported for pivoting about the spindle 41. The locking device 17itself co-operates with a release device 18 which is mounted forpivoting about a spindle 45 on the upper element 31. Manual operation ofthe substantially vertical lever 23 which is readily accessible to thedriver and situated beside the seat, level with the seat cushion, willmake the release device 18, against the action of a spring 19, cause thelocking parts 44 and the yoke 43 of the locking device 17 to pivotclockwise, in FIG. 3, about the spindle 41. The forward toothed ends 21of the locking parts will thus be raised from a co-operating securingposition relative to the toothed rails 32 a which are fastened alongboth sides of the lower element 30 (which is itself fastened to thevehicle). This raising takes place against the action of a spring 24whose ends are fastened to the respective locking part 44 and to theupper element 31. The running track 16 is with advantage placedalongside a longitudinal symmetry plane of the elements 30,31, and theyoke 43 has a more or less symmetrical extent as seen in a horizontalplane, resulting in substantially even distribution of the forces actingupon the rails.

Pivoting the lever 23 about its spindle 45 causes the yoke 43 to beacted upon so that the locking parts 44 can be raised from theirsecuring positions. When this has taken place, the spring 40 urges theupper element 31 rearwards along the plane 33. In cases where the plane33 exhibits a definitely downward forward slope, this takes placeagainst the action of the person sitting in the seat who, by slightlyreducing his weight on the seat, makes the movement possible. The forceexerted by the spring 40 has a component in the vertical directionwhich, depending on the slope of the plane 33, constitutes apredetermined proportion of a statistical mean of the weight of adultpersons.

The yoke 43 and its rear end section 50 which is provided with a rollerand is intended to cooperate with the running track 16 are urged by theaction exerted by the respective springs 40 of the locking parts 44 tobear on the running track 16 during the movement of the element 31 alongthe rails 32 a,32 b to a rear end position. This movement is limited bythe maximum length of the gas spring 40 (see FIG. 2) and/or by a purelymechanical stop, e.g. in the form of a considerable downward bend(depicted in FIGS. 2 and 3) of the running track 16. In this case, noseat position locking takes place at the upper end position, as the seatwill slide down along the plane if the weight load exceeds the aforesaidvertical force component. Only when the rear end device 50 of the yokeleaves the upwardly rounded forward end of the running track 16 can thelocking parts 44 assume a securing position relative to the lowerelement 30. the invention thus makes possible a predetermined drivingposition of the seat which can be finely adjusted in a conventionalmanner by setting the seat in the longitudinal direction by means of therails which are fastened in the horizontal plane 34 to the top of theupper element 31. The seat can also be set in the vertical direction bymeans of a height setting device in the seat frame 35 in a manner shownin FIG. 4, where one can see the seat at a lowered height, as comparedwith FIG. 1.

The lever 23 is so placed as to be operable not only by a person sittingin the seat but also by another person who is in the cab or interior ofthe vehicle and can accordingly easily act upon the lever, inter alia bymeans of his foot, to move the seat to either end position. In a truckcab the seat can thus be moved to the forward position to provide extraclear space in the cab, e.g. to make overnighting in it morecomfortable. The lever 23 may also be provided with a securingarrangement to prevent inadvertent manual operation. The securingarrangement may consist of a recess 47 from which the lever 23 has to beraised by a tilting movement transverse to the forward direction of theseat, against the action of a spring (not depicted here), before thelever can be operated.

The securing device may of course take various different forms, e.g.with the possibility of a securing position in a rear (resting) positionof the seat In driving seat applications, however, it is advantageousfor it to be designed to only secure the lower (driving) position, whilethe resting position has no securing arrangement. This eliminates therisk of the driver being able to set the vehicle in motion while theseat is in the resting position. It has instead the advantageous effectthat the driver glides in a controlled manner down the sloping plane assoon as the seat is sat on in its resting position, whereupon the presetdriving position is automatically assumed. It is of course also possibleto choose from among a number of alternative end positions below the endof the running track, which can be achieved by the release device beingoperated while at the same time the driver suitably increases the weightforce on the seat in order to overcome said vertical force component.This will usually be unnecessary, however, since the seat still has thepossibility of longitudinal setting by movement along the rails in thehorizontal plane which are fastened to the top of the upper element 31.

What is claimed is:
 1. An arrangement for a vehicle seat which ismovable forward and rearwardly relative to a device fastened in thevehicle, the arrangement comprising: a vehicle seat in the vehicle,movable forwardly in the vehicle and movable rearwardly to a rear endposition; a locking device between the vehicle seat and the devicefastened in the vehicle, the locking device being operable to lock aposition of the vehicle seat relative to the device fastened in thevehicle in the forward and rear directions; a release device forpreventing the locking of a position of the locking device; a controldevice connected with the release device for being operated by operationof the release device, the control device cooperating with the lockingdevice during relocation of the seat between the forward and rearwardpositions thereof for freeing the locking device from at least onelocking position thereof between the vehicle seat and the devicefastened in the vehicle so that the seat may be moved rearwardly andforwardly without interference by the locking device; wherein the rearend position of the seat is a resting position of the seat and isrearward enough so that the seat in the resting position is normally notintended for use when the vehicle is in motion.
 2. The arrangement ofclaim 1, wherein the locking device includes a rail between the seat andthe device fastened in the vehicle, the seat being mounted for movementalong the rail, the rail having a plurality of locking positions for theseat located along the rail.
 3. The arrangement of claim 2, wherein therail is oriented in a plane which slopes downwardly in the forwardmovement direction of the seat and of the vehicle, so that the seat ismovable forward and rearward in the longitudinal direction along theslope.
 4. The arrangement of claim 3, wherein the control deviceoperates on the locking device to cause the locking device to lock thevehicle seat against movement at at least one forward position of thevehicle seat, which is a normal position of use of the seat, relative tothe device fastened in the vehicle, during vehicle operation.
 5. Thearrangement of claim 2, wherein the control device is operable fordisabling the locking device from locking the seat relative to thedevice fastened in the vehicle at the rear end position.
 6. Thearrangement of claim 5, wherein the control device comprises a trackwhich extends in a longitudinal direction of the vehicle and is fastenedto the device fastened in the vehicle; the locking device includes afirst portion which engages the track after the seat with the lockingdevice moves rearwardly to and beyond a first rear position prior to therear end position, the locking device further comprising a securingportion which locks to a selected one of the locking positions of therail, the first portion of the locking device and the track being shapedand positioned so that upon engagement of the first portion of thelocking device with the track, the locking device is moved by theengagement with the track for releasing the securing part of the lockingdevice from the locking positions of the rail for enabling the seat tobe moved forwardly and rearwardly along the rail without the lockingportion of the locking device locking to the rail and without lockingthe seat against the movement forwardly and rearwardly.
 7. The lockingdevice of claim 6, further comprising a spindle extending transverselyof the longitudinal direction of the vehicle, the locking device beingpivotally mounted on the spindle with the first portion at one side ofthe pivot spindle and the locking portion at the other side of the pivotspindle.
 8. The arrangement of claim 7, wherein the first portion of thelocking device is rearward of the spindle in the longitudinal directionof the vehicle and the locking portion of the locking device is forwardof the spindle in the longitudinal direction of the vehicle.
 9. Thearrangement of claim 7, wherein the track is above the first portion ofthe locking device when they are engaged and the rail is below thelocking device; means for applying a first force for urging the firstportion of the locking device against the track.
 10. The arrangement ofclaim 7, wherein the track has a front end portion with respect to thelongitudinal direction of the vehicle and positioned for permitting thesecuring portion of the locking device to engage one of the lockingpositions of the rail, and the track has a rear end portion which isrearward with respect to the longitudinal direction of the vehicle andwhich is shaped and positioned for preventing the securing portion ofthe locking device from locking to the rail.
 11. The arrangement ofclaim 10, wherein the track further comprises a stop for preventingfurther rearward movement of the locking device past the stop and forstopping rearward movement of the seat.
 12. The arrangement of claim 7,wherein the release device is pivotally supported on the seat andincludes a lever that extends up from the seat for being moved formoving the release device, and the release device being movable by thelever for moving the locking device.
 13. The arrangement of claim 12,wherein the lever extends substantially vertically upward and has anupper end situated to the side of the seat.
 14. The arrangement of claim6, wherein the track is above the first portion of the locking devicewhen they are engaged and the rail is below the locking device; meansfor applying a first force for urging the first portion of the lockingdevice against the track.
 15. The arrangement of claim 6, wherein thetrack has a front end portion with respect to the longitudinal directionof the vehicle and positioned for permitting the securing portion of thelocking device to engage one of the locking positions of the rail, andthe track has a rear end portion which is rearward with respect to thelongitudinal direction of the vehicle and which is shaped and positionedfor preventing the securing portion of the locking device from lockingto the rail.
 16. The arrangement of claim 1, wherein the control deviceoperates on the locking device to cause the locking device to lock thevehicle seat against movement at least one forward position of thevehicle seat, and the at least one forward position is a normal positionof use of the seat, relative to the device fastened in the vehicle,during vehicle operation.
 17. The arrangement of claim 1, wherein thecontrol device is operable for disabling the locking device from lockingthe seat relative to the device fastened in the vehicle at the rear endposition.
 18. The arrangement of claim 1, further comprising a subframebeneath the seat, the subframe including an upper element, the upperelement having an underside that cooperates with the device fastened tothe vehicle, the subframe upper element having a topside that cooperateswith and supports the seat, and the cooperations on both the undersideand the topside of the upper element of the subframe enable the subframeto move relative to the device fastened in the vehicle and enable theseat to move relative to the subframe, both movements along thelongitudinal direction of the vehicle.
 19. The arrangement of claim 1,wherein the seat height is settable in a substantially verticaldirection.
 20. An arrangement for a vehicle seat which is movableforward and rearwardly relative to a device fastened in the vehicle, thearrangement comprising: a vehicle seat in the vehicle, movable forwardlyin the vehicle and movable rearwardly to a rear end position; a lockingdevice between the vehicle seat and the device fastened in the vehicle,the locking device being operable to lock a position of the vehicle seatrelative to the device fastened in the vehicle in the forward and reardirections; a release device for preventing the locking of a position ofthe locking device; a control device connected with the release devicefor being operated by operation of the release device, the controldevice cooperating with the locking device during relocation of the seatbetween the forward and rearward positions thereof for freeing thelocking device from at least one locking position thereof between thevehicle seat and the device fastened in the vehicle so that the seat maybe moved rearwardly and forwardly without interference by the lockingdevice; further comprising means for applying a first force forassisting the rearward movement of the seat.
 21. The arrangement claim20, further comprising means for applying a second force for opposingthe forward movement of the seat.
 22. The arrangement of claim 21,wherein the locking device includes a rail between the seat and thedevice fastened in the vehicle, the seat being mounted for movementalong the rail, the rail having a plurality of locking positions for theseat located along the rail.
 23. The arrangement of claim 22, whereinthe rail is oriented in a plane which slopes downwardly in the forwardmovement direction of the seat and of the vehicle, so that the seat ismovable forward and rearward in the longitudinal direction along theslope.
 24. An arrangement for a vehicle seat which is movable forwardand rearwardly relative to a device fastened in the vehicle, thearrangement comprising: a vehicle seat in the vehicle, movable forwardlyin the vehicle and movable rearwardly to a rear end position; a lockingdevice between the vehicle seat and the device fastened in the vehicle,the locking device being operable to lock a position of the vehicle seatrelative to the device fastened in the vehicle in the forward and reardirections; a release device for preventing the locking of a position ofthe locking device; a control device connected with the release devicefor being operated by operation of the release device, the controldevice cooperating with the locking device during relocation of the seatbetween the forward and rearward positions thereof for freeing thelocking device from at least one locking position thereof between thevehicle seat and the device fastened in the vehicle so that the seat maybe moved rearwardly and forwardly without interference by the lockingdevice; the control device comprises a track which extends in alongitudinal direction of the vehicle and is fastened to the devicefastened in the vehicle; the locking device includes a first portionwhich engages the track after the seat with the the locking device movesrearwardly to and beyond a first rear position prior to the rear endposition, the locking device further comprising a securing portion whichlocks to a selected one of the locking positions of the tail, the firstportion of the locking device and the track being shaped and positionedso that upon engagement of the first portion of the locking device withthe track the locking device is moved by the engagement with the trackfor releasing the securing part of the locking device from the lockingpositions of the rail for enabling the seat to be moved forwardly andrearwardly along the rail without the locking portion of the lockingdevice locking to the rail and without locking the seat against themovement forwardly and rearwardly.
 25. A subframe for a vehicle seatcomprising: a lower supporting frame which is triangular in shape in avertical plane, has a bottom side that is fastenable to the vehiclefloor and has a top side that is a hypotenuse of the triangular shape,the lower frame being oriented so that the top side is inclined downwardforward; a first rail on the top side of the lower frame and oriented ina forward sloping plane; an upper supporting frame above the lowersupporting frame, the upper frame also is triangular in shape in avertical plane, the upper frame has a bottom side that is a hypotenuseof the triangular shape and that carries a second rail for cooperatingwith the first rail on the lower frame, the upper frame has an upperside on which a seat is supported; at least one of the bottom side ofthe lower frame and the top side of the upper frame having a third railthereon and the respective one of the seat at the top side of the upperframe and the device in the vehicle at the bottom side of the lowerframe having a fourth rail for cooperating with the third rail, both thethird and fourth rails extending generally horizontally, such thatmovement of the third and fourth rails in the longitudinal direction ofthe vehicle and with respect to each other moves the seat generallyalong a horizontal plane; one of the frames including a locking devicefor enabling the locking of the seat in a forward position with respectto the longitudinal direction of the vehicle; a control device operableduring upward and rearward movement of the upper frame with respect tothe lower frame toward an upper resting position of the seat forreleasing the locking device to prevent the locking device from lockingthe seat against forward and rearward movement and for enabling the seatto be moved to the upper resting position that is normally not intendedfor use of the seat when the vehicle is in motion, and for operating thelocking device to become free from locking the seat in at least oneavailable locking position for the seat in the longitudinal direction.26. The subframe of claim 25, further comprising a spring acting on oneof the frames to move one of the frames along the sloping plane of thefirst and second rails.